Aug. 27, 2018 (Phys.org) -- Rising levels of carbon dioxide (CO2) from human activity are making staple crops such as rice and wheat less nutritious and could result in 175 million people becoming zinc deficient and 122 million people becoming protein deficient by 2050, new research shows.

A study led by the Harvard T.H. Chan School of Public Health also found that more than 1 billion women and children could lose a large amount of their dietary iron intake, putting them at increased risk of anemia and other diseases.

"Our research makes it clear that decisions we are making every day -- how we heat our homes, what we eat, how we move around, what we choose to purchase -- are making our food less nutritious and imperiling the health of other populations and future generations," said Sam Myers, lead author of the study and principal research scientist at Harvard Chan School.

The study is to be published online Aug. 27, 2018, in Nature Climate Change.